Crust Crawler Current Measurements

Bioloid robot kit from Korean company Robotis; CM5 controller block, AX12 servos..
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Crust Crawler Current Measurements

Post by FriedV » Thu Nov 15, 2012 5:13 pm

Post by FriedV
Thu Nov 15, 2012 5:13 pm

Here are two pics of Crustcrawler AX18 current measurements.
The blue line ist the data channel, only used for trigger purposes here.
The red line is the total servo current measured as a voltage across a 90 milliOhm resistor in the power line. First pic is sitting on my test bench legs moving free, second is Crusty on the ground. Less difference than I expected in current need. Program executed is Belly Dance fron Testbench.
Image

Image
Friedrich
[/img]
Here are two pics of Crustcrawler AX18 current measurements.
The blue line ist the data channel, only used for trigger purposes here.
The red line is the total servo current measured as a voltage across a 90 milliOhm resistor in the power line. First pic is sitting on my test bench legs moving free, second is Crusty on the ground. Less difference than I expected in current need. Program executed is Belly Dance fron Testbench.
Image

Image
Friedrich
[/img]
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Post by limor » Fri Nov 16, 2012 8:12 pm

Post by limor
Fri Nov 16, 2012 8:12 pm

the shunt is measuring across all servos or one servo ?

what resolution is the graph ?
can you identify impact and torque?
can you run a kalman or other non delay filter on the signal ?
the shunt is measuring across all servos or one servo ?

what resolution is the graph ?
can you identify impact and torque?
can you run a kalman or other non delay filter on the signal ?
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Post by FriedV » Sun Nov 18, 2012 11:10 am

Post by FriedV
Sun Nov 18, 2012 11:10 am

Shunt is across all servos, in the negative supply line from the LiPo 3S.
Resolution of the red graph is +-1V, time res <10msec.
I cannot say anything about impact & torque.
I'll try to take some further measurement with filters.
Friedrich
Shunt is across all servos, in the negative supply line from the LiPo 3S.
Resolution of the red graph is +-1V, time res <10msec.
I cannot say anything about impact & torque.
I'll try to take some further measurement with filters.
Friedrich
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Post by FriedV » Sun Nov 18, 2012 1:11 pm

Post by FriedV
Sun Nov 18, 2012 1:11 pm

Here is the filtered current measurement,
shunt 90mOhms in negative power supply line, all servos.
Servos at rest ~ 322 mA
Servos average ~ 1.5 A
Servos peak ~ 5A
Friedrich
[img]http://robosavvy.com/Builders/FriedV/cur3.jpg[\img]
Here is the filtered current measurement,
shunt 90mOhms in negative power supply line, all servos.
Servos at rest ~ 322 mA
Servos average ~ 1.5 A
Servos peak ~ 5A
Friedrich
[img]http://robosavvy.com/Builders/FriedV/cur3.jpg[\img]
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